Transmission method, reception method, transmission device and reception device

ABSTRACT

One coding method is selected from a plurality of coding methods per data symbol group, an information sequence is encoded by using the selected coding method. The plurality of coding methods includes at least a first coding method and a second coding method. The first coding method is a coding method with a first coding rate for generating a first codeword as a first encoded sequence by using a first parity check matrix. The second coding method is a coding method with a second coding rate different from the first coding rate and obtained after puncturing processing, where a second encoded sequence is generated by performing the puncturing processing on a second codeword by using a second parity check matrix different from the first parity check matrix. A number of bits of the first encoded sequence is equal to a number of bits of the second encoded sequence.

BACKGROUND

1. Technical Field

The present disclosure relates to a broadcast and communication systemwhich uses error correction codes.

2. Description of the Related Art

In a broadcast and communication system which uses radio waves andcables, error correction codes are used in order to improve datareception quality at a reception device. In this case, in considerationof an arithmetic operation scale, it is desirable to use an errorcorrection code of high correction performance. In such a situation, ithas been studied to use an LDPC (Low-Density Parity-Check) code in abroadcast and communication system which uses radio waves and cables. Inconsideration of a variable amount of data transmitted by a transmissiondevice, environment of use (reception in mobile environment or receptionin semi-fixed environment) and the like, it has been studied toconfigure a system in which a block length (code length) of an LDPC codeand a coding rate are variable.

Meanwhile, an LDPC code generating method has been variously studied.For example, NPL 1 describes encoding an information sequence andgenerating and transmitting a codeword of N bits by using an LDPC codedefined by parity check matrix H1 (where a number of columns is N).

Moreover, NPL 2 describes encoding an information sequence andgenerating a codeword of L bits by using an LDPC code defined by paritycheck matrix H2 (where a number of columns is L and a relationship ofN<L holds). Then, NPL 2 describes determining bits not to be transmittedof L-N bits in the codeword of the L bits, and transmitting a sequenceof a rest of N bits (puncturing method).

CITATION LIST Patent Literature

NPL 1: DVB Document A122, Framing structure channel coding andmodulation for a second generation digital terrestrial televisionbroadcasting system (DVB-T2), June 2008.

NPL 2: Q. Dia, Y. Y. Tai, S. Lin, and K. Abdel-Ghaffar, “LDPC codes onpartial geometries: Construction, trapping set structure, andpuncturing,” IEEE Transaction on Information Theory, vol. 59, no. 12,pp. 7898-7914, December 2013.

SUMMARY

In one general aspect, the techniques disclosed here feature atransmission method using a plurality of coding methods. Thetransmission method include selecting one coding method from a pluralityof coding methods per data symbol group, encoding an informationsequence by using the selected coding method to obtain an encodedsequence, modulating the encoded sequence to obtain data symbols, andtransmitting a transmission frame that includes a plurality of datasymbol groups, each of the plurality of data symbol group including theobtained data symbols. The plurality of coding methods includes at leasta first coding method and a second coding method. The first codingmethod is a coding method with a first coding rate for generating afirst encoded sequence by coding a first codeword using a first paritycheck matrix. The second coding method is a coding method with a secondcoding rate that is different from the first coding rate and is codingrate after puncturing processing, in which a second encoded sequence isgenerated by performing the puncturing processing on a second codewordby using a second parity check matrix that is different from the firstparity check matrix. Then, a number of bits of the first encodedsequence is equal to a number of bits of the second encoded sequence.

Additional benefits and advantages of the disclosed embodiments willbecome apparent from the specification and drawings. The benefits and/oradvantages may be individually obtained by the various embodiments andfeatures of the specification and drawings, which need not all beprovided in order to obtain one or more of such benefits and/oradvantages.

It should be noted that general or specific embodiments may beimplemented as a system, a method, an integrated circuit, a computerprogram, a storage medium, or any selective combination thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view illustrating an example of a configuration of areception device and a transmission device which use radio waves;

FIG. 2 is a view illustrating an example of a configuration of anencoder;

FIG. 3 is a view illustrating an example of an operation of thetransmission device when puncturing is used;

FIG. 4 is a view illustrating an example of an operation of thereception device when puncturing is used;

FIG. 5 is a view illustrating an example of a coding method selected fora code length and a coding rate;

FIG. 6 is a view illustrating an example of a coding method selected fora code length and a coding rate;

FIG. 7 is a view illustrating an example of a coding method selected fora code length and a coding rate;

FIG. 8 is a view illustrating an example of a coding method selected fora code length and a coding rate;

FIG. 9 is a view illustrating an example of a coding method selected fora code length;

FIG. 10 is a view illustrating an example of a coding method selectedfor a code length;

FIG. 11 is a view illustrating an example of a configuration of a frametransmitted by the transmission device;

FIG. 12 is a view illustrating an example of a coding method selectedfor a coding rate;

FIG. 13 is a view illustrating an example of a coding method selectedfor a coding rate;

FIG. 14 is a view illustrating an example of a coding method selectedfor a coding rate;

FIG. 15 is a view illustrating an example of a coding method selectedfor a code length and a coding rate;

FIG. 16 is a view illustrating an example of a coding method selectedfor a code length and a coding rate;

FIG. 17 is a view illustrating an example of a configuration of atransmission device;

FIG. 18 is a view illustrating an example of a frame configuration of amodulated signal transmitted by the transmission device;

FIG. 19 is a view illustrating an example of a configuration of aportion related to a control information demodulator and a decoder; and

FIG. 20 is a view illustrating an example of a frame configuration of amodulated signal transmitted by the transmission device.

DESCRIPTION OF EMBODIMENT

The present disclosure relates to a setting of an LDPC code used in abroadcast and communication system in which a block length (code length)and a coding rate are variable and which uses radio waves and cables,such that a reception device obtains higher data reception quality inthe broadcast and communication system.

One aspect of the present disclosure is a transmission method using aplurality of coding methods. The transmission method includes anencoding step of selecting one coding method from a plurality of codingmethods by a unit of a data symbol group, encoding an informationsequence by using the selected coding method, and obtaining an encodedsequence, a modulation step of modulating the encoded sequence andobtaining a data symbol, and a transmission step of transmitting atransmission frame configured to include a plurality of data symbolgroups including a plurality of the data symbols. The plurality ofcoding methods includes at least a first coding method and a secondcoding method. The first coding method is a coding method of a firstcoding rate for forming a generated first codeword into a first encodedsequence by using a first parity check matrix. The second coding methodis a coding method of a second coding rate different from the firstcoding rate and obtained after puncturing processing, in which a secondencoded sequence is generated by performing the puncturing processing ona generated second codeword by using a second parity check matrixdifferent from the first parity check matrix. Then, a number of bits ofthe first encoded sequence is equal to a number of bits of the secondencoded sequence.

One aspect of the present disclosure is a reception method using aplurality of decoding methods. The reception method includes ademodulation step of demodulating a received signal, and a decoding stepof performing error correction decoding on a plurality of receptionvalues generated by the demodulation. The received signal includes aplurality of data symbol groups including a plurality of data symbolsand configures a frame, and the data symbols are encoded by switchingcoding methods by a unit of the data symbol groups. When the pluralityof reception values is values encoded by a first coding method, a firstdecoding method corresponding to the first coding method is applied tothe plurality of reception value. Moreover, when the plurality ofreception values is values encoded by a second coding method,depuncturing processing is applied to the plurality of reception values,and a second decoding method corresponding to the second coding methodis applied to a plurality of values obtained after the depuncturingprocessing. The first coding method is a coding method of a first codingrate for forming a generated first codeword into a first encodedsequence by using a first parity check matrix. The second coding methodis a coding method of a second coding rate different from the firstcoding rate and obtained after puncturing processing, in which a secondencoded sequence is generated by performing the puncturing processing ona generated second codeword by using a second parity check matrixdifferent from the first parity check matrix. Then, a number of bits ofthe first encoded sequence is equal to a number of bits of the secondencoded sequence.

One aspect of the present disclosure is a transmission device using aplurality of coding methods. The transmission device includes an encoderthat selects one coding method from a plurality of coding methods by aunit of a data symbol group, encodes an information sequence by usingthe selected coding method, and obtains an encoded sequence a modulatorthat modulates the encoded sequence and obtains a data symbol and atransmitter that transmits a transmission frame configured to include aplurality of data symbol groups including a plurality of the datasymbols. The plurality of coding methods includes at least a firstcoding method and a second coding method. The first coding method is acoding method of a first coding rate for forming a generated firstcodeword into a first encoded sequence by using a first parity checkmatrix. The second coding method is a coding method of a second codingrate different from the first coding rate and obtained after puncturingprocessing, in which a second encoded sequence is generated byperforming the puncturing processing on a generated second codeword byusing a second parity check matrix different from the first parity checkmatrix. Then, a number of bits of the first encoded sequence is equal toa number of bits of the second encoded sequence.

One aspect of the present disclosure is a reception device using aplurality of decoding methods. The reception device includes ademodulator that demodulates a received signal, and a decoder thatperforms error correction decoding on a plurality of reception valuesgenerated by the demodulator. The received signal includes a pluralityof data symbol groups including a plurality of data symbols andconfigures a frame, and the data symbols are encoded by switching codingmethods by a unit of the data symbol groups. When the plurality ofreception values is values encoded by a first coding method, the decoderapplies a first decoding method corresponding to the first coding methodto the plurality of reception values. Moreover, when the plurality ofreception values is values encoded by a second coding method, thedecoder applies depuncturing processing to the plurality of receptionvalues, and applies the second decoding method corresponding to thesecond coding method to a plurality of values obtained after thedepuncturing processing. The first coding method is a coding method of afirst coding rate for forming a generated first codeword into a firstencoded sequence by using a first parity check matrix. The second codingmethod is a coding method of a second coding rate different from thefirst coding rate and obtained after puncturing processing, in which asecond encoded sequence is generated by performing the puncturingprocessing on a generated second codeword by using a second parity checkmatrix different from the first parity check matrix. Then, a number ofbits of the first encoded sequence is equal to a number of bits of thesecond encoded sequence.

FIG. 1 illustrates an example of a configuration of a system whichincludes transmission device 100 and reception device 150, and whichuses radio waves. Note that FIG. 1 illustrates the system which usesradio waves. However, the system is not limited to this, and may be asystem which uses cables (coaxial cables, cables, light or the like).

Encoder 103 receives an input of information 101 and control information102, performs error correction coding based on information of a codeincluded in control information 102 and used for the error correctioncoding by a transmission device, such as information of a coding rateand a code length (block length), and outputs data 104 obtained afterthe error correction coding.

Puncturing unit 105 receives an input of control information 102 anddata 104 obtained after the error correction coding, determines whetheror not to puncture data 104 obtained after the error correction coding(whether or not to delete part of a bit sequence) based on theinformation of the code included in control information 102 and used forthe error correction coding by the transmission device such asinformation of a coding rate and a code length (block length), andoutputs data 106.

Interleaver 107 receives an input of control information 102 and data106, rearranges data based on information included in controlinformation 102 and related to an interleaving method, and outputsrearranged data 108.

Mapper 109 receives an input of control information 102 and rearrangeddata 108, performs mapping based on information included in controlinformation 102 and related to a modulation method, and outputs basebandsignal 110.

Radio unit 112 receives an input of control information 102, basebandsignal 110 and pilot signal 111. Radio unit 112 performs processing suchas inserting a control information symbol demodulated from controlinformation 102 by a receiver (including information related to amodulation method, an error correction coding method or the like), apilot symbol and the like into a data symbol, and generates a frame.Moreover, radio unit 112 performs signal processing based on controlinformation 102 (for example, radio unit 112 performs signal processingbased on OFDM (Orthogonal Frequency Division Multiplexing) when OFDM isused, or performs signal processing based on an MIMO (MultipleInput-Multiple-Output) method when the MIMO method is used, or performsprocessing such as frequency conversion, band limitation andamplification), and outputs transmission signal 113. Transmission signal113 is output as a radio wave from antenna 114 (note that a number ofantennas described herein is two, but is not limited to this).

FIG. 1 illustrates an example of a configuration of reception device 150which receives a modulated signal transmitted by transmission device100.

Radio unit 153 performs processing such as frequency conversion onreceived signal 152 received at antenna 151, and outputs baseband signal154.

Synchronizer 155 receives an input of baseband signal 154, performsprocessing for frequency synchronization and time synchronization byusing a pilot symbol, a preamble and the like included in a basebandsignal, and outputs synchronization signal 156.

Channel estimator 157 receives an input of baseband signal 154, performschannel estimation by using a pilot symbol, a preamble and the likeincluded in a baseband signal, and outputs channel estimation signal 15.

Control information demodulator 159 receives an input of baseband signal154, demodulates a control information symbol included in the basebandsignal, and outputs control information signal 160.

Demodulator 161 receives an input of baseband signal 154,synchronization signal 156, channel estimation signal 158 and controlinformation signal 160, calculates, for example, a log likelihood ratioof each bit of a data symbol included in baseband signal 154 by usingsynchronization signal 156 and channel estimation signal 158 based oninformation included in control information signal 160 and related to atransmission method such as a modulation method, and outputs loglikelihood ratio signal 162.

Deinterleaver 163 receives an input of control information signal 160and log likelihood ratio signal 162, rearranges an order of loglikelihood ratios based on information included in control informationsignal 160 and related to an interleaving method, and outputs rearrangedlog likelihood ratio signal 164.

Insertion unit 165 receives an input of control information signal 160,and determines whether the transmission device has performed puncturingor has not performed the puncturing (whether the transmission device hasdeleted part of a bit sequence or has not deleted part of the bitsequence) based on information of a block length (code length) and acoding rate of an error correction code in control information signal160.

When it is determined that the “transmission device has performed thepuncturing,” insertion unit 165 inserts into rearranged log likelihoodratio signal 164 a log likelihood ratio (for example, a value of “0”)corresponding to a bit punctured (deleted) by the transmission device.

When it is determined that the “transmission device has not performedthe puncturing,” insertion unit 165 does not insert the above-describedlog likelihood ratio.

Then, insertion unit 165 outputs second log likelihood ratio signal 166.

Decoder 167 receives an input of control information signal 160 andsecond log likelihood ratio signal 166, performs error correctiondecoding based on information included in the control information signaland related to an error correction code, and outputs received data 168.Note that according to the present disclosure, since the LDPC code isused, belief propagation (BP) decoding (for example, sum-productdecoding, min-sum decoding or Laired BP decoding) is performed based ona parity check matrix.

An LDPC code will be described. FIG. 2 illustrates a configuration ofthe encoder. When an information sequence is u=(x₁, x₂, . . . , x_(m))(201), an encoded sequence is s=(x₁, x₂, . . . , x_(m), p₁, p₂, . . . ,p_(n)) (203) and a parity check matrix is H, a following equation holds.(m is a natural number, and n is a natural number).

Hs^(T)=0

By using a relationship of the above-described equation, encoder 202receives an input of information sequence u=(x₁, x₂, . . . , x_(m)), andgenerates and outputs encoded sequence s=(x₁, x₂, . . . , x_(m), p₁, p₂,. . . , p_(n)). Note that coding rate R=m/(m+n) holds. Note that (p₁,p₂, . . . , p_(n)) will be referred to as a parity sequence.

Hence, the transmission device transmits a total of m+n bits of (x₁, x₂,. . . , x_(m), p₁, p₂, . . . , p_(n)) as one encoded block.

In this case, a number of rows of parity check matrix H is n, and anumber of columns is m+n.

Note that a case where encoding is performed as in FIG. 2 will bereferred to as the “LDPC coding method which does not performpuncturing.”

Next, the LDPC code using puncturing will be described.

The transmission device determines bits not to be transmitted of y bitsin encoded sequence s=(x₁, x₂, . . . , x_(m), p₁, p₂, . . . , p_(n)) inthe above-described LDPC code, and the transmission device transmits asequence of m+n−y bits other than the determined bits. FIG. 3illustrates a specific example of the LDPC code using puncturing.

In FIG. 3, for example, the transmission device selects a total of ybits of “x₃, . . . , x_(m−2), p₁, . . . , p_(n−1),” determines not totransmit these y bits, and transmits sequence z₁, z₂, z₃, . . . ,z_(m+n−y+2), z_(m+n−y+1), z_(m+n−y) of a total of the m+n−y bits otherthan the bits determined not to be transmitted.

Note that in an example in FIG. 3, the y bits not to be transmitted areselected from both of an information sequence and a parity sequence, butare not limited to this and may be selected only from an informationsequence or may be selected only from a parity sequence. That is, the ybits not to be transmitted may be selected from an encoded sequence inany way.

Hence, the transmission device transmits a total of the m+n−y bits of(z₁, z₂, z₃, . . . , z_(m+n−y+2), z_(m+n−y+1), z_(m+n−y)) as one encodedblock.

Note that hereinafter, the above-described method will be referred to asthe “LDPC coding method using puncturing.”

FIG. 4 illustrates an example of an operation example of the receptiondevice when the transmission device transmits data as illustrated inFIG. 3.

The reception device receives sequence z₁, z₂, z₃, . . . , z_(m+n−y+2),z_(m+n−y+1), z_(m+n−y), and sets log likelihood ratios of these bits toLz₁, Lz₂, Lz₃, . . . , Lz_(m+n−y+2), Lz_(m+n−y+1), Lz_(m+n−y).

As illustrated in FIG. 4, the reception device sets to “0 (zero)” thelog likelihood ratio of each bit of a total of the y bits of “x₃, . . ., x_(m−2), p₁, . . . , p_(n−1)” which are not transmitted by thetransmission device. Therefore, the “log likelihood ratio of x₃=0, . . ., the log likelihood ratio of x_(m−2)=0, the log likelihood ratio ofp₁=0, . . . , the log likelihood ratio of p_(n−1)=0” are inserted.Hence, log likelihood ratios Lx₁, Lx₂, Lx₃, . . . , Lx_(m−2), Lx_(m−1),Lx_(m), Lp₁, Lp₂, Lp₃, . . . , Lp_(n−2), Lp_(n−1), Lp_(n) of bits of x₁,x₂, x₃, . . . , x_(m−2), x_(m−1), x_(m), p₁, p₂, p₃, . . . , p_(n−2),p_(n−1), p_(n) are obtained. Then, the reception device performs BPdecoding by using Lx₁, Lx₂, Lx₃, . . . , Lx_(m−2), Lx_(m−1), Lx_(m),Lp₁, Lp₂, Lp₃, . . . , Lp_(n−2), Lp_(n−1), Lp_(n), and obtains receiveddata.

Next, a case where the transmission device supports a bits and 13 bitsas numbers of bits of one encoded block for coding rate R=γ will bediscussed. Note that α and β are natural numbers, and α<β holds.

In a case of the “LDPC coding method using puncturing,” an LDPC code ofa code length (block length) of α+v bits (where v is a natural number)and coding rate q (where q<y) is used for coding rate R=y and the a bitsof one encoded block. Subsequently, puncturing is performed. Note thatthis method will be referred to as “method #1.”

Similarly, in a case of the “LDPC coding method using puncturing,” anLDPC code of a code length (block length) of β+u bits (where u is anatural number) and coding rate q (where q<γ) is used for coding rateR=γ and the β bits of one encoded block. Subsequently, puncturing isperformed. Note that this method will be referred to as “method #2.”

By contrast with this, in a case of the “LDPC coding method which doesnot perform puncturing,” an LDPC code of a code length (block length) ofthe a bits and coding rate γ is used for coding rate R=γ and the a bitsof one encoded block. Note that this method will be referred to as“method #3.”

Similarly, in a case of the “LDPC coding method which does not performpuncturing,” an LDPC code of a code length (block length) of the β bitsand coding rate γ is used for coding rate R=γ and the β bits of oneencoded block. Note that this method will be referred to as “method #4.”

Under a condition that a relationship of α<β holds, discussion will bemade.

In this case, when the number of bits of one encoded block is the abits, there is a case where “method #1” provides higher data receptionquality than data reception quality in “method #3.”

On the other hand, when the number of bits of one encoded block is β,there is a case where “method #4” provides higher data reception qualitythan data reception quality in “method #2.”

A reason for this will be described below.

In a case of “method #1,” an LDPC code with a code length (block length)of α+v bits that is larger than α is used in order to realize the a bitsas the number of bits of one encoded block. Here, α<β holds, and in acase where α is small, the degree of contribution made by an added valueof v in the code length (block length) of the α+v bits is large. Forthis reason, there is a case where high data reception quality isobtained when “method #1” is used, as compared to data reception qualityobtained when the LDPC code of the code length (block length) of the abits is used.

On the other hand, in a case of “method #2,” an LDPC code with a codelength (block length) of β+u bits that is larger than β is used torealize the β bits as the number of bits of one encoded block. Here, α<βholds, and in a case where β is large, the degree of contribution madeby an added value in the code length (block length) of the β+u bits issmall, and puncturing causes significant deterioration. Therefore, thereis a case where use of an LDPC code of the code length (block length) ofthe β bits, that is, “method #4” provides higher data reception qualitythan data reception quality in “method #2.”

Here, data reception quality depends on specific values of α and β.(Moreover, the values of α and β are likely to change depending on acoding rate.) A specific example will be described below.

FIG. 5 is an example illustrating which one of “method #A” and “method#B” is used for number of bits z and a coding rate of one encoded block.Note that in a case of “method #A,” a coding rate means a coding rateobtained after puncturing (after bits not to be transmitted are deleted)instead of a coding rate of the LDPC code.

In the example in FIG. 5, in a case of one encoded block z=8100 bits,“method #A” realizes all of coding rates 5/15, 6/15, 7/15, 8/15, 9/15,10/15, 11/15, 12/15 and 13/15.

Then, in a case of one encoded block z=16200 bits, “method #A” realizesall of coding rates 5/15, 6/15, 7/15, 8/15, 9/15, 10/15, 11/15, 12/15and 13/15.

In a case of one encoded block z=64800 bits, “method #B” realizes all ofcoding rates 5/15, 6/15, 7/15, 8/15, 9/15, 10/15, 11/15, 12/15 and13/15.

In this case, when a number of bits of one encoded block is a certainvalue, “method #A in a case of coding rate a” and “method #A in a caseof coding rate b” (where a≠b) will be described. (Here, any of codingrate a and coding rate b is a coding rate obtained after puncturing(after bits not to be transmitted are deleted).) In this case, there area and b satisfying one of following conditions.

Condition 5-1: An LDPC code that is a base of “method #A in a case ofcoding rate a” and an LDPC code that is a base of “method #A in a caseof coding rate b” are different codes.

Condition 5-2: A parity check matrix of an LDPC code that is a base of“method #A in a case of coding rate a” and a parity check matrix of anLDPC code that is a base of “method #A in a case of coding rate b” aredifferent.

Condition 5-3: A number of rows of a parity check matrix of an LDPC codethat is a base of “method #A in a case of coding rate a” and a number ofrows of a parity check matrix of an LDPC code that is a base of “method#A in a case of coding rate b” are different.

Condition 5-4: A number of columns of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of columns of a parity check matrix of an LDPC code that is abase of “method #A in a case of coding rate b” are different.

A number of bits of one encoded block is z bits. Note that z is anatural number.

The z bits of one encoded block are realized by using an “LDPC codingmethod using puncturing.” Note that this method will be referred to as“method #A.”

The z bits of one encoded block are realized by using an “LDPC codingmethod which does not perform puncturing.” Note that this method will bereferred to as “method #B.”

The transmission device and the reception device set a coding rate fromcoding rates illustrated in FIG. 6, and also select one encoded blockfrom the number of bits of one encoded block illustrated in FIG. 6.

FIG. 6 is an example illustrating which one of “method #A” and “method#B” is used for number of bits z and a coding rate of one encoded block.Note that in a case of “method #A,” a coding rate means a coding rateobtained after puncturing (after bits not to be transmitted are deleted)instead of a coding rate of the LDPC code.

In the example in FIG. 6, in a case of one encoded block z=8100 bits,“method #A” realizes all of coding rates 5/15, 6/15, 7/15, 8/15, 9/15,10/15, 11/15, 12/15 and 13/15.

Then, in a case of one encoded block z=16200 bits, “method #B” realizesall of coding rates 5/15, 6/15, 7/15, 8/15, 9/15, 10/15, 11/15, 12/15and 13/15.

In a case of one encoded block z=64800 bits, “method #B” realizes all ofcoding rates 5/15, 6/15, 7/15, 8/15, 9/15, 10/15, 11/15, 12/15 and13/15.

In this case, when a number of bits of one encoded block is a certainvalue, “method #A in a case of coding rate a” and “method #A in a caseof coding rate b” (where a≠b) will be discussed. (Here, any of codingrate a and coding rate b is a coding rate obtained after puncturing(after bits not to be transmitted are deleted).) In this case, there area and b satisfying one of following conditions.

Condition 6-1: An LDPC code that is a base of “method #A in a case ofcoding rate a” and an LDPC code that is a base of “method #A in a caseof coding rate b” are different codes.

Condition 6-2: A parity check matrix of an LDPC code that is a base of“method #A in a case of coding rate a” and a parity check matrix of anLDPC code that is a base of “method #A in a case of coding rate b” aredifferent.

Condition 6-3: A number of rows of a parity check matrix of an LDPC codethat is a base of “method #A in a case of coding rate a” and a number ofrows of a parity check matrix of an LDPC code that is a base of “method#A in a case of coding rate b” are different.

Condition 6-4: A number of columns of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of columns of a parity check matrix of an LDPC code that is abase of “method #A in a case of coding rate b” are different.

A number of bits of one encoded block is z bits. Note that z is anatural number.

The z bits of one encoded block are realized by using an “LDPC codingmethod using puncturing.” Note that this method will be referred to as“method #A.”

The z bits of one encoded block are realized by using an “LDPC codingmethod which does not perform puncturing.” Note that this method will bereferred to as “method #B.”

The transmission device and the reception device set a coding rate fromcoding rates illustrated in FIG. 7, and also select one encoded blockfrom the number of bits of one encoded block illustrated in FIG. 7.

FIG. 7 is an example illustrating which one of “method #A” and “method#B” is used for number of bits z and a coding rate of one encoded block.Note that in a case of “method #A,” a coding rate means a coding rateobtained after puncturing (after bits not to be transmitted are deleted)instead of a coding rate of the LDPC code.

In the example in FIG. 7, when one encoded block z is 1000 bits or moreand 9000 bits or less, “method #A” realizes all of coding rates 5/15,6/15, 7/15, 8/15, 9/15, 10/15, 11/15, 12/15 and 13/15.

Then, when one encoded block z is 10000 bits or more and 20000 bits orless, “method #A” realizes all of coding rates 5/15, 6/15, 7/15, 8/15,9/15, 10/15, 11/15, 12/15 and 13/15.

When one encoded block z is 50000 bits or more and 70000 bits or less,“method #B” realizes all of coding rates 5/15, 6/15, 7/15, 8/15, 9/15,10/15, 11/15, 12/15 and 13/15.

In this case, when a number of bits of one encoded block is a certainvalue, “method #A in a case of coding rate a” and “method #A in a caseof coding rate b” (where a≠b) will be discussed. (Here, any of codingrate a and coding rate b is a coding rate obtained after puncturing(after bits not to be transmitted are deleted).) In this case, there area and b satisfying one of following conditions.

Condition 7-1: An LDPC code that is a base of “method #A in a case ofcoding rate a” and an LDPC code that is a base of “method #A in a caseof coding rate b” are different codes.

Condition 7-2: A parity check matrix of an LDPC code that is a base of“method #A in a case of coding rate a” and a parity check matrix of anLDPC code that is a base of “method #A in a case of coding rate b” aredifferent.

Condition 7-3: A number of rows of a parity check matrix of an LDPC codethat is a base of “method #A in a case of coding rate a” and a number ofrows of a parity check matrix of an LDPC code that is a base of “method#A in a case of coding rate b” are different.

Condition 7-4: A number of columns of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of columns of a parity check matrix of an LDPC code that is abase of “method #A in a case of coding rate b” are different.

A number of bits of one encoded block is z bits. Note that z is anatural number.

The z bits of one encoded block are realized by using an “LDPC codingmethod using puncturing.” Note that this method will be referred to as“method #A.”

The z bits of one encoded block are realized by using an “LDPC codingmethod which does not perform puncturing.” Note that this method will bereferred to as “method #B.”

The transmission device and the reception device set a coding rate fromcoding rates illustrated in FIG. 8, and also select one encoded blockfrom the number of bits of one encoded block illustrated in FIG. 8.

FIG. 8 is an example illustrating which one of “method #A” and “method#B” is used for number of bits z and a coding rate of one encoded block.Note that in a case of “method #A,” a coding rate means a coding rateobtained after puncturing (after bits not to be transmitted are deleted)instead of a coding rate of the LDPC code.

In the example in FIG. 8, when number of bits z of one encoded block is1000 bits or more and 9000 bits or less, “method #A” realizes all ofcoding rates 5/15, 6/15, 7/15, 8/15, 9/15, 10/15, 11/15, 12/15 and13/15.

Then, when number of bits z of one encoded block is 10000 bits or moreand 20000 bits or less, “method #B” realizes all of coding rates 5/15,6/15, 7/15, 8/15, 9/15, 10/15, 11/15, 12/15 and 13/15.

When one encoded block z is 50000 bits or more and 70000 bits or less,“method #B” realizes all of coding rates 5/15, 6/15, 7/15, 8/15, 9/15,10/15, 11/15, 12/15 and 13/15.

In this case, when a number of bits of one encoded block is a certainvalue, “method #A in a case of coding rate a” and “method #A in a caseof coding rate b” (where a≠b) will be discussed. (Here, any of codingrate a and coding rate b is a coding rate obtained after puncturing(after bits not to be transmitted are deleted).) In this case, there area and b satisfying one of following conditions.

Condition 8-1: An LDPC code that is a base of “method #A in a case ofcoding rate a” and an LDPC code that is a base of “method #A in a caseof coding rate b” are different codes.

Condition 8-2: A parity check matrix of an LDPC code that is a base of“method #A in a case of coding rate a” and a parity check matrix of anLDPC code that is a base of “method #A in a case of coding rate b” aredifferent.

Condition 8-3: A number of rows of a parity check matrix of an LDPC codethat is a base of “method #A in a case of coding rate a” and a number ofrows of a parity check matrix of an LDPC code that is a base of “method#A in a case of coding rate b” are different.

Condition 8-4: A number of columns of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of columns of a parity check matrix of an LDPC code that is abase of “method #A in a case of coding rate b” are different.

A number of bits of one encoded block is z bits. Note that z is anatural number.

The z bits of one encoded block are realized by using an “LDPC codingmethod using puncturing.” Note that this method will be referred to as“method #A.”

The z bits of one encoded block are realized by using an “LDPC codingmethod which does not perform puncturing.” Note that this method will bereferred to as “method #B.”

The transmission device and the reception device select one encodedblock from the number of bits of one encoded block illustrated in FIG.9. Note that a coding rate can also be set.

FIG. 9 is an example illustrating which one of “method #A” and “method#B” is used for number of bits z of one encoded block. Note that in acase of “method #A,” a coding rate means a coding rate obtained afterpuncturing (after bits not to be transmitted are deleted) instead of acoding rate of the LDPC code.

In the example in FIG. 9, when one encoded block z is less than 20000bits, “method #A” is used.

Then, when one encoded block z is 20000 bits or more, “method #B” isused.

In this case, when a number of bits of one encoded block is a certainvalue, “method #A in a case of coding rate a” and “method #A in a caseof coding rate b” (where a≠b) will be discussed. (Here, any of codingrate a and coding rate b is a coding rate obtained after puncturing(after bits not to be transmitted are deleted).) In this case, there area and b satisfying one of following conditions.

Condition 9-1: An LDPC code that is a base of “method #A in a case ofcoding rate a” and an LDPC code that is a base of “method #A in a caseof coding rate b” are different codes.

Condition 9-2: A parity check matrix of an LDPC code that is a base of“method #A in a case of coding rate a” and a parity check matrix of anLDPC code that is a base of “method #A in a case of coding rate b” aredifferent.

Condition 9-3: A number of rows of a parity check matrix of an LDPC codethat is a base of “method #A in a case of coding rate a” and a number ofrows of a parity check matrix of an LDPC code that is a base of “method#A in a case of coding rate b” are different.

Condition 9-4: A number of columns of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of columns of a parity check matrix of an LDPC code that is abase of “method #A in a case of coding rate b” are different.

A number of bits of one encoded block is z bits. Note that z is anatural number.

The z bits of one encoded block are realized by using an “LDPC codingmethod using puncturing.” Note that this method will be referred to as“method #A.”

The z bits of one encoded block are realized by using an “LDPC codingmethod which does not perform puncturing.” Note that this method will bereferred to as “method #B.”

The transmission device and the reception device select one encodedblock from the number of bits of one encoded block illustrated in FIG.10. Note that a coding rate can also be set.

FIG. 10 is an example illustrating which one of “method #A” and “method#B” is used for number of bits z of one encoded block. Note that in acase of “method #A,” a coding rate means a coding rate obtained afterpuncturing (after bits not to be transmitted are deleted) instead of acoding rate of the LDPC code.

In the example in FIG. 10, when one encoded block z is less than 10000bits, “method #A” is used.

Then, when one encoded block z is 10000 bits or more, “method #B” isused.

In this case, when a number of bits of one encoded block is a certainvalue, “method #A in a case of coding rate a” and “method #A in a caseof coding rate b” (where a≠b) will be discussed. (Here, any of codingrate a and coding rate b is a coding rate obtained after puncturing(after bits not to be transmitted are deleted).) In this case, there area and b satisfying one of following conditions.

Condition 10-1: An LDPC code that is a base of “method #A in a case ofcoding rate a” and an LDPC code that is a base of “method #A in a caseof coding rate b” are different codes.

Condition 10-2: A parity check matrix of an LDPC code that is a base of“method #A in a case of coding rate a” and a parity check matrix of anLDPC code that is a base of “method #A in a case of coding rate b” aredifferent.

Condition 10-3: A number of rows of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of rows of a parity check matrix of an LDPC code that is a baseof “method #A in a case of coding rate b” are different.

Condition 10-4: A number of columns of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of columns of a parity check matrix of an LDPC code that is abase of “method #A in a case of coding rate b” are different.

FIG. 11 is an example of a configuration of a frame transmitted by thetransmission device, and in FIG. 11 a horizontal axis is time. FIG. 11is an example where a transmission method which uses, for example, asingle carrier is used. However, when a multi-carrier method such asOFDM (Orthogonal Frequency Division Multiplexing) is used, there is aplurality of carriers in a frequency direction, and there are symbols ina carrier direction. Moreover, when, for example, a space-time code oran MIMO (Multiple Input-Multiple-Output) method is used, there is aframe per stream.

In FIG. 11, preamble 1101 uses, for example, a PSK (Phase Shift Keying)modulated symbol which is known in a transmitter and a receiver. Thereceiver performs frequency offset estimation, frequencysynchronization, time synchronization, frame synchronization, channelestimation, signal detection and the like by using this symbol.

Control information symbol 1102 includes, for example, information of anerror correction code method (a code length, a block length of oneencoded block, and a coding rate of one encoded block) used forgenerating a data symbol, information of a modulation method used forgenerating a data symbol, and information related to the transmissionmethod. The reception device obtains the control information bydemodulating this symbol, and, consequently, demodulation and errorcorrection decoding of the data symbol become possible.

Moreover, whether or not to insert a log likelihood ratio described withreference to FIG. 1 is controlled based on the information obtained incontrol information symbol 1102.

Data symbol 1103 is generated based on an error correction coding method(a code length, a block length of one encoded block, and a coding rateof one encoded block), a modulation method and a transmission methodselected by the transmission device. Note that although not illustratedin FIG. 11, a symbol such as a pilot symbol may be inserted into symbolsdescribed as control information symbol 1102 and data symbol 1103.

Hence, a frame configuration is not limited to the configuration in FIG.11.

The transmission device can select a value of one encoded block of datato be transmitted from a plurality of values and provides a threshold.When one encoded block of data transmitted by the transmission device isthe threshold or more, the transmission device selects the “LDPC codingmethod which does not perform puncturing” and transmits data. When theone encoded block is less than the threshold, the transmission deviceselects the “LDPC coding method using puncturing” and transmits data.Consequently, the reception device can obtain an effect of obtaininghigh data reception quality at any value of one encoded block.

Next, a case where the transmission device supports coding rates α, βand γ for numbers of bits δ of one encoded block. Note that α, β and γare values larger than 0 and smaller than 1, and α<β<γ holds. Note thata coding rate in a case of the “LDPC coding method using puncturing”means a coding rate obtained after puncturing (after bits not to betransmitted are deleted).

In a case of the “LDPC coding method using puncturing,” an LDPC code ofa code length (block length) of δ+u bits (where u is a natural number)and coding rate a (where a<α) is used for coding rate R=α and the δ bitsof one encoded block. Subsequently, puncturing is performed. Note thatthis method will be referred to as “method $1.”

Similarly, in a case of the “LDPC coding method using puncturing,” anLDPC code of a code length (block length) of δ+v bits (where v is anatural number) and coding rate b (where b<β) is used for coding rateR=β and the δ bits of one encoded block. Subsequently, puncturing isperformed. Note that this method will be referred to as “method $2.”

In a case of the “LDPC coding method using puncturing,” an LDPC code ofa code length (block length) of δ+w bits (where w is a natural number)and coding rate c (where c<γ) is used for coding rate R=γ and the δ bitsof one encoded block. Subsequently, puncturing is performed. Note thatthis method will be referred to as “method $3.”

By contrast with this, in a case of the “LDPC coding method which doesnot perform puncturing,” an LDPC code of a code length (block length) ofδ bits and coding rate α is used for coding rate R=α and the δ bits ofone encoded block. Note that this method will be referred to as “method$4.”

Similarly, in a case of the “LDPC coding method which does not performpuncturing,” an LDPC code of a code length (block length) of the δ bitsand coding rate β is used for coding rate R=β and the δ bits of oneencoded block. Note that this method will be referred to as “method $5.”

In a case of the “LDPC coding method which does not perform puncturing,”an LDPC code of a code length (block length) of the δ bits and codingrate γ is used for coding rate R=γ and the δ bits of one encoded block.Note that this method will be referred to as “method $6.”

Under a condition that a relationship of α<β<γ holds, discussion will bemade.

In this case, when the coding rate is as small as α, there is a casewhere “method $4” provides higher data reception quality than datareception quality in “method $1.”

When the coding rate is an intermediate value like β, there is a casewhere “method $2” provides higher data reception quality than datareception quality in “method $5.”

When the coding rate is as large as γ, there is a case where “method $6”provides higher data reception quality than data reception quality in“method $3.”

A reason for this will be described below.

Performance of an LDPC code of a low coding rate tends to have anexpanding difference from Shannon limits. Hence, in a case of a small(low) coding rate such as coding rate α and in a case of “method $1,” acoding rate of a base LDPC code is smaller than α. For this reason, thedifference from Shannon limits is large and, when puncturing isperformed, it is difficult to obtain good data reception quality.

In a case of an intermediate coding rate such as coding rate β and in acase of “method $2,” there is a large difference between a Shannon limitof the coding rate of the base LDPC code and a Shannon limit of thepunctured coding rate. For this reason, performance of the base LDPCcode makes contribution, and “method $2” is highly likely to providehigh data reception quality.

In a case of a high coding rate such as coding rate γ and in a case of“method $3,” there is a small difference between a Shannon limit of thecoding rate of the base LDPC code and a Shannon limit of the puncturedcoding rate. For this reason, “method $3” is likely to have difficultyin obtaining high data reception quality. However, as compared to“method $6,” “method $3” has an advantage of being capable of using asparse parity check matrix. Consequently, “method $3” is likely toprovide good reception quality.

Here, data reception quality depends on specific values of α, β and γ.(Moreover, the values of α, β and γ are likely to change depending on avalue of one encoded block.) A specific example will be described below.

A number of bits of one encoded block is z bits. Note that z is anatural number.

The z bits of one encoded block are realized by using an “LDPC codingmethod using puncturing.” Note that this method will be referred to as“method #A.”

The z bits of one encoded block are realized by using an “LDPC codingmethod which does not perform puncturing.” Note that this method will bereferred to as “method #B.”

The transmission device and the reception device select a coding ratefrom coding rates illustrated in FIG. 12. Note that the number of bitsof one encoded block can also be set.

FIG. 12 is an example illustrating which one of “method #A” and “method#B” is used when number of bits z of one encoded block is set to acertain value. Note that in a case of “method #A,” a coding rate means acoding rate obtained after puncturing (after bits not to be transmittedare deleted) instead of a coding rate of the LDPC code.

In FIG. 12, e and f are larger than 0 and smaller than 1, and e<f holds.

In an example in FIG. 12, when the coding rate is less than fin a caseof one encoded block z (z is a natural number), “method #B” is used.

Then, when the coding rate is e or more and f or less in a case of oneencoded block z (z is a natural number), “method #A” is used.

Then, when the coding rate is larger than f in a case of one encodedblock z (z is a natural number), “method #B” is used.

There are a and b satisfying a coding rate of e or more and f or less,and the transmission device can select “method #A in a case of codingrate a” and “method #A in a case of coding rate b.” (Here, any of codingrate a and coding rate b is a coding rate obtained after puncturing(after bits not to be transmitted are deleted).) (Here, a≠b holds.)

In this case, there are a and b satisfying one of following conditions.

Condition 12-1: An LDPC code that is a base of “method #A in a case ofcoding rate a” and an LDPC code that is a base of “method #A in a caseof coding rate b” are different codes.

Condition 12-2: A parity check matrix of an LDPC code that is a base of“method #A in a case of coding rate a” and a parity check matrix of anLDPC code that is a base of “method #A in a case of coding rate b” aredifferent.

Condition 12-3: A number of rows of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of rows of a parity check matrix of an LDPC code that is a baseof “method #A in a case of coding rate b” are different.

Condition 12-4: A number of columns of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of columns of a parity check matrix of an LDPC code that is abase of “method #A in a case of coding rate b” are different.

Note that “number of bits z of one encoded block is set to a certainvalue” as described above.

Hence, there may be one or more types of coding rates which are lessthan f, there may be two or more types of coding rates which are e ormore and f or less and there may be one or more types of coding rateswhich are larger than f.

A number of bits of one encoded block is z bits. Note that z is anatural number.

The z bits of one encoded block are realized by using an “LDPC codingmethod using puncturing.” Note that this method will be referred to as“method #A.”

The z bits of one encoded block are realized by using an “LDPC codingmethod which does not perform puncturing.” Note that this method will bereferred to as “method #B.”

The transmission device and the reception device select a coding ratefrom coding rates illustrated in FIG. 13. Note that the number of bitsof one encoded block can also be set.

FIG. 13 is an example illustrating which one of “method #A” and “method#B” is used for number of bits z of one encoded block. Note that in acase of “method #A,” a coding rate means a coding rate obtained afterpuncturing (after bits not to be transmitted are deleted) instead of acoding rate of the LDPC code.

In FIG. 13, g is larger than 0 and is smaller than 1.

In an example in FIG. 13, when the coding rate is less than g in a caseof one encoded block z (z is a natural number), “method #B” is used.

Then, when the coding rate is g or more in a case of one encoded block z(z is a natural number), “method #A” is used.

There are a and b satisfying a coding rate of g or more, thetransmission device can select “method #A in a case of coding rate a”and “method #A in a case of coding rate b.” (Here, any of coding rate aand coding rate b is a coding rate obtained after puncturing (after bitsnot to be transmitted are deleted).) (Here, a≠b holds.) In this case,there are a and b satisfying one of following conditions.

Condition 13-1: An LDPC code that is a base of “method #A in a case ofcoding rate a” and an LDPC code that is a base of “method #A in a caseof coding rate b” are different codes.

Condition 13-2: A parity check matrix of an LDPC code that is a base of“method #A in a case of coding rate a” and a parity check matrix of anLDPC code that is a base of “method #A in a case of coding rate b” aredifferent.

Condition 13-3: A number of rows of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of rows of a parity check matrix of an LDPC code that is a baseof “method #A in a case of coding rate b” are different.

Condition 13-4: A number of columns of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of columns of a parity check matrix of an LDPC code that is abase of “method #A in a case of coding rate b” are different.

Note that “number of bits z of one encoded block is set to a certainvalue” as described above.

Hence, there may be one or more types of coding rates which are lessthan g, and two or more types of coding rates which are g or more.

A number of bits of one encoded block is z bits. Note that z is anatural number.

The z bits of one encoded block are realized by using an “LDPC codingmethod using puncturing.” Note that this method will be referred to as“method #A.”

The z bits of one encoded block are realized by using an “LDPC codingmethod which does not perform puncturing.” Note that this method will bereferred to as “method #B.”

The transmission device and the reception device select a coding ratefrom coding rates illustrated in FIG. 14. Note that the number of bitsof one encoded block can also be set.

FIG. 14 is an example illustrating which one of “method #A” and “method#B” is used for number of bits z of one encoded block. Note that in acase of “method #A,” a coding rate means a coding rate obtained afterpuncturing (after bits not to be transmitted are deleted) instead of acoding rate of the LDPC code.

In FIG. 14, h is larger than 0 and is smaller than 1.

In an example in FIG. 14, when the coding rate is less than h in a caseof one encoded block z (z is a natural number), “method #A” is used.

Then, when the coding rate is h or more in a case of one encoded block z(z is a natural number), “method #B” is used.

There are a and b satisfying a coding rate of less than h, and thetransmission device can select “method #A in a case of coding rate a”and “method #A in a case of coding rate b.” (Here, any of coding rate aand coding rate b is a coding rate obtained after puncturing (after bitsnot to be transmitted are deleted).) (Here, a≠b holds.) In this case,there are a and b satisfying one of following conditions.

Condition 14-1: An LDPC code that is a base of “method #A in a case ofcoding rate a” and an LDPC code that is a base of “method #A in a caseof coding rate b” are different codes.

Condition 14-2: A parity check matrix of an LDPC code that is a base of“method #A in a case of coding rate a” and a parity check matrix of anLDPC code that is a base of “method #A in a case of coding rate b” aredifferent.

Condition 14-3: A number of rows of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of rows of a parity check matrix of an LDPC code that is a baseof “method #A in a case of coding rate b” are different.

Condition 14-4: A number of columns of a parity check matrix of an LDPCcode that is a base of “method #A in a case of coding rate a” and anumber of columns of a parity check matrix of an LDPC code that is abase of “method #A in a case of coding rate b” are different.

Note that “number of bits z of one encoded block is set to a certainvalue” as described above.

Hence, there may be two or more types of coding rates which are lessthan h, and one or more types of coding rates which are h or more.

Operations of the transmission device and the reception device are asdescribed above with reference to FIGS. 1, 11 and the like.

The transmission device sets to a predetermined value a value of oneencoded block of data to be transmitted, and provides a threshold. Thetransmission device selects the “LDPC coding method which does notperform puncturing” when the coding rate is the threshold or more, andselects the “LDPC coding method using puncturing” when the coding rateis less than the threshold. Alternatively, the transmission deviceselects the “LDPC coding method using puncturing” when the coding rateis the threshold or more, and selects the “LDPC coding method which doesnot perform puncturing” when the coding rate is less than the threshold.Consequently, the reception device can obtain an effect of obtaininghigher data reception quality at any coding rate.

Exemplary Embodiment A

In the present exemplary embodiment, examples of configurations of acontrol information transmission method and transmission device andconfigurations of a control information reception method and receptiondevice according to above-described exemplary embodiment will bedescribed.

FIG. 15 illustrates an example of parameters of an error correction codeaccording to the present exemplary embodiment. A number of bits of oneencoded block is z bits. Note that z is a natural number.

The z bits of one encoded block are realized by using an “LDPC codingmethod using puncturing.” This method will be referred to as “method#A.”

The z bits of one encoded block are realized by using an “LDPC codingmethod which does not perform puncturing.” This method will be referredto as “method #B.”

The z bits of one encoded block will be described supplementally.

In a case of the “LDPC coding method using puncturing,” coding isperformed on an LDPC code (LDPC block code) with a code length (blocklength) of z+γ bits (γ is a natural number), and data of the z+γ bits isobtained. Then, the γ bits are punctured (the γ bits not to betransmitted are determined), and data of the z bits to be transmitted isobtained. In a case of the “LDPC coding method using puncturing,” the “zbits of one encoded block” means that “this data to be transmitted is ofthe z bits.”

In a case of the “LDPC coding method which does not perform puncturing,”coding is performed on an LDPC code (LDPC block code) with a code lengthof z bits, and data of the z bits is obtained and transmitted. The “zbits of one encoded block” means that “this data to be transmitted is ofthe z bits.”

FIG. 15 is an example illustrating which one of “method #A” and “method#B” is used for number of bits z and a coding rate of one encoded block.Note that in a case of “method #A,” a coding rate means a coding rateobtained after puncturing (after bits not to be transmitted are deleted)instead of a coding rate of the LDPC code (instead of a coding rateobtained before puncturing).

In the example in FIG. 15, in a case of one encoded block z=16200 bits,“method #A” realizes coding rates 5/15, 6/15, 7/15 and 8/15, and “method#B” realizes coding rates 9/15, 10/15, 11/15, 12/15 and 13/15.

Then, in a case of one encoded block z=64800 bits, “method #B” realizescoding rates 5/15, 6/15, 7/15, 8/15, 9/15, 10/15, 11/15, 12/15 and13/15.

Features in FIG. 15 are such that the “transmission device and thereception device support number of bits x (x is a natural number) of oneencoded block and number of bits y (y is a natural number) of oneencoded block. When x>y holds, “method #B” is used at all coding ratesin a case of number of bits x (x is a natural number) of one encodedblock, and there are coding rates which adopt “method #A” in a case ofnumber of bits y of one encoded block.” Therefore, in FIG. 15, in a caseof z=16200 bits, “method #A” is used at coding rates 5/15, 6/15, 7/15and 8/15 (however, FIG. 15 is only an example, and, in a case of z=16200bits, there only needs to be coding rates which adopt “method #A”).

Moreover, as described above, FIG. 15 may be interpreted such that“number of bits x (x is a natural number) of one encoded block andnumber of bits y (y is a natural number) of one encoded block aresupported at a certain coding rate. When x>y holds, “method #B” is usedin a case of number of bits x of one encoded block, and “method #A” isused in a case of number of bits y of one encoded block” (however, atanother coding rate, “method #B” may be used for both of number of bitsx of one encoded block and number of bits y of one encoded block).

FIG. 16 is an example different from FIG. 15 and illustrating which oneof “method #A” and “method #B” is used for number of bits z and a codingrate of one encoded block. Note that in a case of “method #A,” a codingrate means a coding rate obtained after puncturing (after bits not to betransmitted are deleted) instead of a coding rate of the LDPC code(instead of a coding rate obtained before puncturing).

In the example in FIG. 16, when one encoded block z is 10000 bits ormore and 20000 bits or less, “method #A” realizes coding rates 5/15,6/15 and 7/15, and “method #B” realizes coding rates 8/15, 9/15, 10/15,11/15, 12/15 and 13/15.

Then, when number of bits z of one encoded block is 50000 bits or moreand 70000 bits or less, “method #B” realizes coding rates 5/15, 6/15,7/15, 8/15, 9/15, 10/15, 11/15, 12/15 and 13/15.

As described above, features of FIG. 16 are such that “number of bits x(x is a natural number) of one encoded block and number of bits y (y isa natural number) of one encoded block are supported at a certain codingrate. When x>y holds, “method #B” is used in a case of number of bits xof one encoded block, and “method #A” is used in a case of number ofbits y of one encoded block” (however, at another coding rate, “method#B” may be used for both of number of bits x of one encoded block andnumber of bits y of one encoded block).

FIG. 17 illustrates an example of a configuration of the transmissiondevice, and the same operations as those in FIG. 1 will be assigned thesame reference numerals and will not be described. Encoder 103 in FIG.17 receives an input of information 101 and control information 102, andperforms error correction processing based on FIG. 15 or 16.

For example, a case where the error correction coding is performed basedon FIG. 15 will be described.

Control information 102 includes information of number of bits z of oneencoded block of an error correction code (LDPC code), and informationof a coding rate used for error correction coding (a coding rateobtained after puncturing when puncturing is performed).

Here, in a case of “method #A,” a coding rate used for error correctioncoding means a coding rate obtained after puncturing (after bits not tobe transmitted are deleted) instead of a coding rate of the LDPC code(instead of a coding rate obtained before puncturing). Then, in a caseof “method #B,” the coding rate used for error correction coding means acoding rate of an LDPC code.

Therefore, for example, based on FIG. 15, encoder 103 receives an inputof information 101 and control information 102. Encoder 103 performserror correction coding (including puncturing processing) on information101 based on the information of number of bits z of one encoded block ofthe error correction code (LDPC code) included in control information102, and the information of the coding rate used for the errorcorrection coding included in control information 102. Encoder 103outputs data 104 obtained after the error correction coding.

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=16200 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 5/15, encoder103 performs encoding in “method #A” corresponding to the coding rate5/15 (as described above, encoder 103 performs encoding of an LDPC code,and performs puncturing (encoder 103 selects bits not to be transmittedand determines data to be transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=16200 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 6/15, encoder103 performs encoding in “method #A” corresponding to the coding rate6/15 (as described above, encoder 103 performs encoding of an LDPC code,and performs puncturing (encoder 103 selects bits not to be transmittedand determines data to be transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=16200 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 7/15, encoder103 performs encoding in “method #A” corresponding to the coding rate7/15 (as described above, encoder 103 performs encoding of an LDPC code,and performs puncturing (encoder 103 selects bits not to be transmittedand determines data to be transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=16200 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 8/15, encoder103 performs encoding in “method #A” corresponding to the coding rate8/15 (as described above, encoder 103 performs encoding of an LDPC code,and performs puncturing (encoder 103 selects bits not to be transmittedand determines data to be transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=16200 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 9/15, encoder103 performs encoding in “method #B” corresponding to the coding rate9/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=16200 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 10/15, encoder103 performs encoding in “method #B” corresponding to the coding rate10/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=16200 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 11/15, encoder103 performs encoding in “method #B” corresponding to the coding rate11/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=16200 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 12/15, encoder103 performs encoding in “method #B” corresponding to the coding rate12/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=16200 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 13/15, encoder103 performs encoding in “method #B” corresponding to the coding rate13/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=64800 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 5/15, encoder103 performs encoding in “method #B” corresponding to the coding rate5/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=64800 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 6/15, encoder103 performs encoding in “method #B” corresponding to the coding rate6/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=64800 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 7/15, encoder103 performs encoding in “method #B” corresponding to the coding rate7/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=64800 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 8/15, encoder103 performs encoding in “method #B” corresponding to the coding rate8/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=64800 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 9/15, encoder103 performs encoding in “method #B” corresponding to the coding rate9/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=64800 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 10/15, encoder103 performs encoding in “method #B” corresponding to the coding rate10/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=64800 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 11/15, encoder103 performs encoding in “method #B” corresponding to the coding rate11/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=64800 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 12/15, encoder103 performs encoding in “method #B” corresponding to the coding rate12/15 (encoder 103 does not perform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates z=64800 bits, and where the information of the coding rateused for error correction coding indicates a coding rate 13/15, encoder103 performs encoding in “method #B” corresponding to the coding rate13/15 (encoder 103 does not perform puncturing as described above).

For example, based on FIG. 16, encoder 103 receives an input ofinformation 101 and control information 102. Encoder 103 performs errorcorrection coding (including puncturing processing) on information 101based on the information of number of bits z of one encoded block of theerror correction code (LDPC code) included in control information 102,and the information of the coding rate used for the error correctioncoding included in control information 102. Encoder 103 outputs data 104obtained after the error correction coding.

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 10000 bits or more and 20000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 5/15, encoder 103 performs encoding in“method #A” corresponding to the coding rate 5/15 (as described above,encoder 103 performs encoding of an LDPC code, and performs puncturing(encoder 103 selects bits not to be transmitted and determines data tobe transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 10000 bits or more and 20000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 6/15, encoder 103 performs encoding in“method #A” corresponding to the coding rate 6/15 (as described above,encoder 103 performs encoding of an LDPC code, and performs puncturing(encoder 103 selects bits not to be transmitted and determines data tobe transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 10000 bits or more and 20000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 7/15, encoder 103 performs encoding in“method #A” corresponding to the coding rate 7/15 (as described above,encoder 103 performs encoding of an LDPC code, and performs puncturing(encoder 103 selects bits not to be transmitted and determines data tobe transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 10000 bits or more and 20000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 8/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 8/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 10000 bits or more and 20000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 9/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 9/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 10000 bits or more and 20000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 10/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 10/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 10000 bits or more and 20000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 11/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 11/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 10000 bits or more and 20000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 12/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 12/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 10000 bits or more and 20000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 13/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 13/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 50000 bits or more and 70000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 5/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 5/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 50000 bits or more and 70000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 6/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 6/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 50000 bits or more and 70000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 7/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 7/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 50000 bits or more and 70000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 8/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 8/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 50000 bits or more and 70000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 9/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 9/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 50000 bits or more and 70000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 10/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 10/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 50000 bits or more and 70000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 11/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 11/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 50000 bits or more and 70000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 12/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 12/15 (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) included in control information102 indicates that “z is 50000 bits or more and 70000 bits or less,” andwhere the information of the coding rate used for error correctioncoding indicates a coding rate 13/15, encoder 103 performs encoding in“method #B” corresponding to the coding rate 13/15 (encoder 103 does notperform puncturing as described above).

Encoded block bit number information generator 1701 receives an input ofcontrol information 102. Encoded block bit number information generator1701 extracts information of number of bits z of one encoded block of anerror correction code (LDPC code) included in control information 102.Encoded block bit number information generator 1701 outputs information1702 of the number of bits of one encoded block for forming a controlinformation symbol.

Coding rate information generator 1703 receives an input of controlinformation 102. Coding rate information generator 1703 extractsinformation of a coding rate used for error correction coding includedin control information 102 (a coding rate obtained after puncturing whenpuncturing is performed). Coding rate information generator 1703 outputsinformation 1704 of the coding rate used for the error correction codingfor forming the control information symbol.

Other control information generator 1705 receives an input of controlinformation 102. Other control information generator 1705 outputscontrol information 1706 for forming a control information symbol otherthan information of the number of bits of one encoded block for forminga control information symbol and information of a coding rate used forerror correction coding for forming a control information symbol.

Control information symbol generator 1707 receives an input ofinformation 1702 of the number of bits of one encoded block, information1704 of a coding rate used for error correction coding, and controlinformation 1706. Control information symbol generator 1707 performsprocessing such as error correction coding and mapping, and outputscontrol information symbol baseband signal 1708.

Radio unit 112 receives an input of control information 102, basebandsignal 110, pilot signal 111 and control information symbol basebandsignal 1708. Based on information related to a frame configurationincluded in control information 102, radio unit 112 generates andoutputs transmission signal 113 which is based on a frame configuration(radio unit 112 performs processing such as inverse Fourier transformand frequency conversion in a case of, for example, using OFDM(Orthogonal Frequency Division Multiplexing)).

FIG. 18 illustrates an example of a frame configuration of a modulatedsignal transmitted by the transmission device in FIG. 17 (an example ofa frame configuration in a case of transmitting one modulated signal).In FIG. 18, a vertical axis indicates time, and a horizontal axisindicates a frequency. For example, in a case of a multi-carrier methodsuch as OFDM (Orthogonal Frequency Division Multiplexing), there is aplurality of carriers. For this reason, it is assumed here that thereare symbols in carrier 0 to carrier 14. Then, in FIG. 18, time $1 totime $8 are indicated.

In FIG. 18, “C” indicates a control information symbol, “P” indicates apilot symbol and “D” indicates a data symbol. As described above withreference to FIG. 17, the control information symbol includesinformation of the number of bits of one encoded block and informationof a coding rate used for error correction coding.

The pilot symbol is a symbol for channel estimation (propagation channelfluctuation estimation), frequency synchronization, timesynchronization, signal detection, frequency offset estimation and thelike performed by the reception device which receives a modulated signaltransmitted by the transmission device. For example, the pilot symbolonly needs to be a symbol modulated by using PSK (Phase Shift Keying)modulation and known in a transmitter and a receiver (or a receiver maybe capable of learning a symbol transmitted by the transmitter byestablishing synchronization).

The data symbol is a symbol for transmitting data generated based on,for example, FIG. 15 or 16 and obtained after error correction coding(note that the number of bits of one encoded block of data obtainedafter error correction coding, and the coding rate used for errorcorrection coding are a number of bits of one encoded block and a codingrate used for error correction coding which are specified by informationof the number of bits of one encoded block and information of a codingrate used for error correction coding included in a control informationsymbol).

Next, an operation of the reception device which receives a modulatedsignal transmitted by the transmission device in FIG. 17 will bedescribed.

A configuration of the reception device which receives a modulatedsignal transmitted by the transmission device in FIG. 17 is as indicatedby 150 in FIG. 1. Operations of control information demodulator 159 anddecoder 167 in reception device 150 in FIG. 1 in particular will bedescribed in detail below.

FIG. 19 is a view illustrating a configuration of a portion related tocontrol information demodulator 159 and decoder 167 in reception device150 in FIG. 1.

Control information demodulator 159 includes one encoded block bitnumber information/coding rate information estimator 1903. One encodedblock bit number information/coding rate information estimator 1903receives an input of baseband signal 1902, and extracts the controlinformation symbol illustrated in FIG. 18. Further, one encoded blockbit number information/coding rate information estimator 1903 obtainsinformation of the number of bits of one encoded block and informationof a coding rate used for error correction coding, from the controlinformation symbol. One encoded block bit number information/coding rateinformation estimator 1903 outputs estimation signal 1904 of theinformation of the number of bits of one encoded block and theinformation of the coding rate used for error correction coding.

Puncture bit log likelihood ratio generator 1905 receives an input ofestimation signal 1904 of the information of the number of bits of oneencoded block and the information of the coding rate used for errorcorrection coding. Puncture bit log likelihood ratio generator 1905determines whether a method used by the transmission device to generatedata of a data symbol is “method #A” or “method #B” described withreference to FIGS. 15 and 16, from the information of the number of bitsof one encoded block and the information of the coding rate used forerror correction coding based on FIG. 15 or 16. When it is determinedthat the method is “method #B,” puncture bit log likelihood ratiogenerator 1905 generates and outputs log likelihood ratio 106 of bitscorresponding to bits (bits which are not transmitted by thetransmission device) punctured by the transmission device.

When, for example, the transmission device in FIG. 17 performs encodingbased on FIG. 15 and transmits a modulated signal, puncture bit loglikelihood ratio generator 1905 determines as follows.

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=16200 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 5/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=16200 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 6/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=16200 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 7/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=16200 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 8/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=16200 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 9/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=16200 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 10/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=16200 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 11/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=16200 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 12/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=16200 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 13/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=64800 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 5/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=64800 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 6/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=64800 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 7/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=64800 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 8/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=64800 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 9/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=64800 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 10/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=64800 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 11/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=64800 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 12/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates z=64800 bits, and that the information of the coding rate usedfor error correction coding indicates a coding rate 13/15, puncture bitlog likelihood ratio generator 1905 determines that the method used bythe transmission device to generate data of a data symbol is “method#B.”

When, for example, the transmission device in FIG. 17 performs encodingbased on FIG. 16 and transmits a modulated signal, puncture bit loglikelihood ratio generator 1905 determines as follows.

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 10000 bits or more and 20000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 5/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 10000 bits or more and 20000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 6/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 10000 bits or more and 20000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 7/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 10000 bits or more and 20000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 8/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 10000 bits or more and 20000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 9/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 10000 bits or more and 20000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 10/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 10000 bits or more and 20000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 11/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 10000 bits or more and 20000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 12/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 10000 bits or more and 20000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 13/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 50000 bits or more and 70000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 5/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 50000 bits or more and 70000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 6/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 50000 bits or more and 70000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 7/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 50000 bits or more and 70000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 8/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 50000 bits or more and 70000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 9/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 50000 bits or more and 70000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 10/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 50000 bits or more and 70000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 11/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 50000 bits or more and 70000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 12/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code)indicates “z being 50000 bits or more and 70000 bits or less,” and thatthe information of the coding rate used for error correction codingindicates a coding rate 13/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of a data symbol is “method #B.”

Exemplary Embodiment B

A modification of exemplary embodiment A will be described.

An example illustrating which one of “method #A” and “method #B” is usedfor number z of one encoded block and a coding rate is as described withreference to FIGS. 15 and 16 in exemplary embodiment A, and will not bedescribed.

A configuration of a transmission device is as described with referenceto FIG. 17 in exemplary embodiment A, and will be described partially.

FIG. 20 is a view illustrating an example of a frame configuration of amodulated signal transmitted by the transmission device in FIG. 17. InFIG. 20, a vertical axis indicates a frequency, and a horizontal axisindicates time. Then, since a transmission method using a multi-carriersuch as an OFDM method is used, there is a plurality of carriers on thevertical axis of frequency.

FIG. 20 illustrates first preamble 2001, second preamble 2002, datasymbol group #1 2003, data symbol group #2 2004, and data symbol group#3 2005.

The data symbol groups will be described. In a case of a broadcastsystem, a data symbol group may be allocated per video/audio. Forexample, a symbol for transmitting a first video/audio stream is datasymbol group #1 (2003). A symbol for transmitting a second video/audiostream is data symbol group #2 (2004). A symbol for transmitting a thirdvideo/audio stream is data symbol group #3 (note that a PLP (PhysicalLayer Pipe) may be referred to as a data symbol group. In this case,data symbol group #1 may be referred to as PLP #1, data symbol group #2may be referred to as a PLP #2, and data symbol group #3 may be referredto as PLP #3).

First preamble 2001 and second preamble 2002 include a symbol forperforming frequency synchronization and time synchronization (forexample, a PSK (Phase Shift Keying) symbol having signal constellationin an in-phase I-quadrature plane known in a transmitter and areceiver), a symbol for transmitting transmission method information ofeach data symbol group (information for identifying an SISO(Single-Input Single-Output) method, an MISO (Multiple-InputSingle-Output) method and an MIMO method)), a symbol for transmittinginformation related to an error correction code of each data symbolgroup (for example, a code length (the number of bits of one encodedblock) and a coding rate), a symbol for transmitting information relatedto a modulation method of each data symbol group (in a case of the MISOmethod or the MIMO method, since there is a plurality of streams, aplurality of modulation methods is specified), a symbol for transmittingtransmission method information of the first and second preambles, asymbol for transmitting information related to a modulation method ofthe first and second preambles, a symbol for transmitting informationrelated to a method for inserting a pilot symbol, and a symbol fortransmitting information related to a method for suppressing PAPR(Peak-to-Average Power Ratio).

Similar to exemplary embodiment A, in the present exemplary embodiment,it is assumed that information of the number of bits of one encodedblock of each data symbol group and information of a coding rate usedfor error correction coding of each data symbol group are included infirst preamble (2001) and/or second preamble (2002). Therefore, in acase of the frame configuration in FIG. 20, information of the number ofbits of one encoded block of data symbol group #1 and information of acoding rate used for error correction coding of data symbol group #1,information of the number of bits of one encoded block of data symbolgroup #2 and information of a coding rate used for error correctioncoding of data symbol group #2, and information of the number of bits ofone encoded block of data symbol group #3 and information of a codingrate used for error correction coding of data symbol group #3 areincluded in first preamble (2001) and/or second preamble (2002).

Therefore, for example, based on FIG. 15, encoder 103 receives an inputof information 101 and control information 102. Encoder 103 performserror correction coding (including puncturing processing) on information101 based on the information of number of bits z of one encoded block ofthe error correction code (LDPC code) included in control information102, and the information of the coding rate used for the errorcorrection coding included in control information 102. Encoder 103outputs data 104 obtained after the error correction coding.

In this case, the following is performed on each data symbol group. Notethat in a case of the frame configuration in FIG. 20, the following iscarried out assuming that X is 1, 2 and 3.

In a case where information of number of bits z of one encoded block ofthe error correction code (LDPC code) of data symbol group #X includedin control information 102 indicates z=16200 bits, and where informationof a coding rate used for error correction coding of data symbol group#X indicates a coding rate 5/15, encoder 103 performs encoding in“method #A” corresponding to the coding rate 5/15 in order to generatedata for forming data symbol group #X (as described above, encoder 103performs encoding of an LDPC code and performs puncturing (encoder 103selects bits not to be transmitted, and determines data to betransmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=16200 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 6/15, encoder 103 performsencoding in “method #A” corresponding to the coding rate 6/15 in orderto generate data for forming data symbol group #X (as described above,encoder 103 performs encoding of an LDPC code and performs puncturing(encoder 103 selects bits not to be transmitted, and determines data tobe transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=16200 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 7/15, encoder 103 performsencoding in “method #A” corresponding to the coding rate 7/15 in orderto generate data for forming data symbol group #X (as described above,encoder 103 performs encoding of an LDPC code and performs puncturing(encoder 103 selects bits not to be transmitted, and determines data tobe transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=16200 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 8/15, encoder 103 performsencoding in “method #A” corresponding to the coding rate 8/15 in orderto generate data for forming data symbol group #X (as described above,encoder 103 performs encoding of an LDPC code and performs puncturing(encoder 103 selects bits not to be transmitted, and determines data tobe transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=16200 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 9/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 9/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=16200 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 10/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 10/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=16200 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 11/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 11/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=16200 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 12/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 12/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=16200 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 13/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 13/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=64800 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 5/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 5/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=64800 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 6/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 6/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=64800 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 7/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 7/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=64800 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 8/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 8/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=64800 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 9/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 9/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=64800 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 10/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 10/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=64800 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 11/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 11/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=64800 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 12/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 12/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates z=64800 bits, and wherethe information of a coding rate used for error correction coding ofdata symbol group #X indicates a coding rate 13/15, encoder 103 performsencoding in “method #B” corresponding to the coding rate 13/15 in orderto generate data for forming data symbol group #X (encoder 103 does notperform puncturing as described above).

For example, based on FIG. 16, encoder 103 receives an input ofinformation 101 and control information 102. Encoder 103 performs errorcorrection coding (including puncturing processing) on information 101based on the information of number of bits z of one encoded block of theerror correction code (LDPC code) included in control information 102,and the information of the coding rate used for the error correctioncoding included in control information 102. Encoder 103 outputs data 104obtained after the error correction coding.

In this case, the following is performed on each data symbol group. Notethat in a case of the frame configuration in FIG. 20, the following iscarried out assuming that X is 1, 2 and 3.

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 10000 bits ormore and 20000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 5/15, encoder 103 performs encoding in “method #A”corresponding to the coding rate 5/15 in order to generate data forforming data symbol group #X (as described above, encoder 103 performsencoding of an LDPC code and performs puncturing (encoder 103 selectsbits not to be transmitted, and determines data to be transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 10000 bits ormore and 20000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 6/15, encoder 103 performs encoding in “method #A”corresponding to the coding rate 6/15 in order to generate data forforming data symbol group #X (as described above, encoder 103 performsencoding of an LDPC code and performs puncturing (encoder 103 selectsbits not to be transmitted, and determines data to be transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 10000 bits ormore and 20000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 7/15, encoder 103 performs encoding in “method #A”corresponding to the coding rate 7/15 in order to generate data forforming data symbol group #X (as described above, encoder 103 performsencoding of an LDPC code and performs puncturing as described above(encoder 103 selects bits not to be transmitted, and determines data tobe transmitted)).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 10000 bits ormore and 20000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 8/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 8/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 10000 bits ormore and 20000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 9/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 9/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 10000 bits ormore and 20000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 10/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 10/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 10000 bits ormore and 20000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 11/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 11/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 10000 bits ormore and 20000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 12/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 12/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 10000 bits ormore and 20000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 13/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 13/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 50000 bits ormore and 70000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 5/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 5/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 50000 bits ormore and 70000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 6/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 6/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 50000 bits ormore and 70000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 7/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 7/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 50000 bits ormore and 70000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 8/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 8/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 50000 bits ormore and 70000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 9/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 9/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 50000 bits ormore and 70000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 10/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 10/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 50000 bits ormore and 70000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 11/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 11/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 50000 bits ormore and 70000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 12/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 12/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

In a case where the information of number of bits z of one encoded blockof the error correction code (LDPC code) of data symbol group #Xincluded in control information 102 indicates that “z is 50000 bits ormore and 70000 bits or less,” and where the information of a coding rateused for error correction coding of data symbol group #X indicates acoding rate 13/15, encoder 103 performs encoding in “method #B”corresponding to the coding rate 13/15 in order to generate data forforming data symbol group #X (encoder 103 does not perform puncturing asdescribed above).

Next, an operation of the reception device which receives a modulatedsignal transmitted by the transmission device in FIG. 17 will bedescribed.

A configuration of the reception device which receives a modulatedsignal transmitted by the transmission device in FIG. 17 is as indicatedby 150 in FIG. 1. Operations of control information demodulator 159 anddecoder 167 in reception device 150 in FIG. 1 in particular will bedescribed in detail below.

FIG. 19 is a view illustrating a configuration of a portion related tocontrol information demodulator 159 and decoder 167 in reception device150 in FIG. 1.

Control information demodulator 159 includes one encoded block bitnumber information/coding rate information estimator 1903. One encodedblock bit number information/coding rate information estimator 1903receives an input of baseband signal 1902, and extracts the firstpreamble and (or) the second preamble illustrated in FIG. 20. Further,one encoded block bit number information/coding rate informationestimator 1903 obtains information of the number of bits of one encodedblock and information of a coding rate used for error correction codingfrom the first preamble and (or) the second preamble. One encoded blockbit number information/coding rate information estimator 1903 outputsestimation signal 1904 of the information of the number of bits of oneencoded block and the information of the coding rate used for errorcorrection coding.

In a case of the present exemplary embodiment, the transmission devicein FIG. 17 transmits a modulated signal of the frame configuration basedon FIG. 20, and reception device 150 in FIG. 1 receives this modulatedsignal. In this case, reception device 150 in FIG. 1 performs ademodulating and decoding operation for obtaining data of a necessarydata symbol group among a plurality of data symbol groups. Therefore,control information demodulator 159 obtains “information of the numberof bits of one encoded block and information of a coding rate used forerror correction coding” of the necessary data symbol group. Controlinformation demodulator 159 outputs estimation signal 1904 ofinformation of the number of bits of one encoded block and theinformation of the coding rate used for error correction coding.

Puncture bit log likelihood ratio generator 1905 receives an input ofestimation signal 1904 of the information of the number of bits of oneencoded block and the information of the coding rate used for errorcorrection coding. Puncture bit log likelihood ratio generator 1905determines whether a method used by the transmission device to generatedata of a data symbol is “method #A” or “method #B” described withreference to FIGS. 15 and 16, from the information of the number of bitsof one encoded block and the information of the coding rate used forerror correction coding based on FIG. 15 or 16. When it is determinedthat the method is “method #B,” puncture bit log likelihood ratiogenerator 1905 generates and outputs log likelihood ratio 106 of bitscorresponding to bits (bits which are not transmitted by thetransmission device) punctured in the transmission device. Note thatthat “when it is determined that the method is “method #B,” puncture bitlog likelihood ratio generator 1905 generates and outputs log likelihoodratio 106 of bits corresponding to bits (bits which are not transmittedby the transmission device) punctured in the transmission device” asdescribed above, but puncture bit log likelihood ratio generator 1905generates and outputs log likelihood ratio 106 of bits corresponding tobits (bits which are not transmitted by the transmission device)punctured for a necessary data symbol group.

For example, in a case where the transmission device in FIG. 17 performsencoding based on FIG. 15, and transmits a modulated signal of the frameconfiguration based on FIG. 20, puncture bit log likelihood ratiogenerator 1905 determined as follows for each data symbol group (X is 1,2 and 3).

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=16200 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 5/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=16200 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 6/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=16200 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 7/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=16200 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 8/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=16200 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 9/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=16200 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 10/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=16200 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 11/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=16200 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 12/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=16200 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 13/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=64800 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 5/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=64800 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 6/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=64800 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 7/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=64800 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 8/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=64800 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 9/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=64800 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 10/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=64800 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 11/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=64800 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 12/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates z=64800 bits, and that the information ofthe coding rate used for error correction coding of data symbol group #Xindicates a coding rate 13/15, puncture bit log likelihood ratiogenerator 1905 determines that the method used by the transmissiondevice to generate data of data symbol group #X is “method #B.”

For example, in a case where the transmission device in FIG. 17 performsencoding based on FIG. 16, and transmits a modulated signal of the frameconfiguration based on FIG. 20, puncture bit log likelihood ratiogenerator 1905 determines as follows for each data symbol group (X is 1,2 and 3).

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 10000 bits or more and 20000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate5/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 10000 bits or more and 20000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate6/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 10000 bits or more and 20000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate7/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #A.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 10000 bits or more and 20000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate8/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 10000 bits or more and 20000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate9/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 10000 bits or more and 20000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate10/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 10000 bits or more and 20000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate11/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 10000 bits or more and 20000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate12/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 10000 bits or more and 20000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate13/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 50000 bits or more and 70000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate5/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 50000 bits or more and 70000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate6/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 50000 bits or more and 70000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate7/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 50000 bits or more and 70000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate8/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 50000 bits or more and 70000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate9/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 50000 bits or more and 70000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate10/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 50000 bits or more and 70000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate11/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 50000 bits or more and 70000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate12/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

In a case where estimation signal 1904 of the information of the numberof bits of one encoded block and the information of the coding rate usedfor error correction coding indicates that the information of number ofbits z of one encoded block of an error correction code (LDPC code) ofdata symbol group #X indicates “z being 50000 bits or more and 70000bits or less,” and that the information of the coding rate used forerror correction coding of data symbol group #X indicates a coding rate13/15, puncture bit log likelihood ratio generator 1905 determines thatthe method used by the transmission device to generate data of datasymbol group #X is “method #B.”

The examples Illustrating which one of “method #A” and “method #B” isused for number of bits z of one encoded block and the coding rate aredescribed in exemplary embodiment A and exemplary embodiment B withreference to FIGS. 15 and 16. However, allocation of “method #A” and“method #B” for number of bits z of one encoded block and the codingrate is not limited to those in FIGS. 15 and 16. The features of FIGS.15 and 16 described in exemplary embodiment A only need to be satisfied.For example, in FIG. 15, z=16800 bits and a coding rate 8/15 may be usedfor “method #B,” and z=16800 bits and a coding rate 9/15 may be used for“method #A.”

Moreover, in exemplary embodiment B, the frame configuration of amodulated signal transmitted by the transmission device is describedwith reference to FIG. 20. However, the frame configuration is notlimited to this, and may be, for example, a frame configurationincluding one or more data symbol groups or two or more data symbolgroups.

The broadcast (or communication) system according to the presentdisclosure is described in the above-described exemplary embodiments.However, the present disclosure is not limited to this.

As a matter of course, a plurality of the exemplary embodiments andother contents described herein may be combined and carried out.

Moreover, each exemplary embodiment and the other contents are onlyexamples. For example, while a “modulation method, an error correctioncoding method (an error correction code, a code length, a coding rateand the like to be used), control information and the like” areexemplified, each exemplary embodiment and the other contents can becarried out with the same configuration even when other types of a“modulation method, an error correction coding method (an errorcorrection code, a code length, a coding rate and the like to be used),control information and the like” are applied.

As for a modulation method, even when a modulation method other than themodulation methods described herein is used, the exemplary embodimentsand other contents described herein can be carried out. For example,APSK (Amplitude Phase Shift Keying) (such as 16 APSK, 64 APSK, 128 APSK,256 APSK, 1024 APSK and 4096 APSK), PAM (Pulse Amplitude Modulation)(such as 4 PAM, 8 PAM, 16 PAM, 64 PAM, 128 PAM, 256 PAM, 1024 PAM and4096 PAM), PSK (Phase Shift Keying) (such as BPSK, QPSK, 8 PSK, 16 PSK,64 PSK, 128 PSK, 256 PSK, 1024 PSK and 4096 PSK), and QAM (QuadratureAmplitude Modulation) (such as 4 QAM, 8 QAM, 16 QAM, 64 QAM, 128 QAM,256 QAM, 1024 QAM and 4096 QAM) may be applied. In each modulationmethod, uniform mapping or non-uniform mapping may be performed (anymapping may be performed).

Moreover, a method for arranging 16 signal points, 64 signal points orthe like in an I-Q plane (a modulation method having 16 signal points,64 signal points or the like) is not limited to the signal constellationmethod of the modulation methods described herein. Therefore, a functionof outputting an in-phase component and a quadrature component based ona plurality of bits is a function in a mapper.

The disclosure described herein is applicable to multi-carriertransmission methods such as the OFDM method, and is also applicable tosingle carrier transmission methods (For example, in a case of amulti-carrier method, symbols are arranged also in a frequency axis, butin a case of a single carrier, symbols are arranged only in a timedirection.) Moreover, a spread spectrum communication method is alsoapplicable to baseband signals by using spreading codes.

Herein, a reception device of a terminal and an antenna may beconfigured separately. For example, the reception device includes aninterface which receives through a cable an input of a signal receivedat the antenna or a signal obtained by performing frequency conversionon a signal received at the antenna, and the reception device performssubsequent processing. Moreover, data and information obtained by thereception device are subsequently converted into a video or a sound tobe displayed on a display (monitor) or to be output from a speaker.Further, the data and the information obtained by the reception devicemay be subjected to signal processing related to a video or a sound (thesignal processing may not be performed), and may be output from an RCAterminal (a video terminal or an audio terminal), a USB (UniversalSerial Bus), a USB 2, a USB 3, an HDMI (registered trademark)(High-Definition Multimedia Interface), an HDMI (registered trademark)2, a digital terminal or the like of the reception device. Moreover, thedata and the information obtained by the reception device are modulatedby using wireless communication methods (Wi-Fi (registered trademark)(IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, IEEE 802.11n, IEEE802.11ac,IEEE 802.11ad and the like), WiGiG, Bluetooth (registered trademark) andthe like) or wired communication methods (optical communication andpower line communication), and these pieces of information may betransmitted to other apparatuses. In this case, a terminal includes atransmission device which transmits information (in this case, theterminal may transmit data including the data and information obtainedby the reception device, or may generate modified data from the data andinformation obtained by the reception device and transmit the modifieddata).

Herein, a communication and broadcast apparatus such as a broadcaststation, a base station, an access point, a terminal and a mobile phoneis considered to include the transmission device. In this case, acommunication apparatus such as a television, a radio, a terminal, apersonal computer, a mobile phone, an access point and a base station isconsidered to include the reception device. Moreover, the transmissiondevice and the reception device according to the present disclosure areeach also considered to be an apparatus which has a communicationfunction and which can be connected via any interface to a device thatexecutes applications such as a television, a radio, a personal computerand a mobile phone.

Moreover, in the present exemplary embodiment, symbols other than a datasymbol, for example, a pilot symbol (a preamble, a unique word, apostamble, a reference symbol and the like), and a control informationsymbol may be arranged in frames in any way. Then, these symbols arecalled a pilot symbol or a control information symbol here, but thesesymbols may be called in any way and the function itself is important.

Hence, for example, a symbol is called a control information symbol, buthow to call the symbol is not limited to this, and the symbol may becalled in another way. This symbol is a symbol for transmitting controlinformation such as information of a transmission method (for example, atransmission method, a modulation method, a coding rate of an errorcorrection code, a code length of an error correction code, a method forconfiguring a frame and a Fourier transform method (size)).

Moreover, the pilot symbol only needs to be a symbol modulated by usingPSK modulation and known in a transmitter and a receiver (or a receivermay be capable of learning a symbol transmitted by the transmitter byestablishing synchronization). The receiver performs frequencysynchronization, time synchronization, channel estimation (of eachmodulated signal) (estimation of CSI (Channel State Information), signaldetection and like by using this symbol.

Moreover, the control information symbol is a symbol for transmittinginformation (for example, a coding rate of a modulation method, an errorcorrection coding method, and the error correction coding method usedfor communication, and setting information in an upper layer) whichneeds to be transmitted to a communicating party for realizingcommunication other than data communication (such as applicationcommunication).

Note that the present disclosure is not limited to each exemplaryembodiment, and can be variously modified and carried out. For example,the case where each exemplary embodiment is carried out as acommunication device is described, but each exemplary embodiment is notlimited to this, and can be performed by using this communication methodas software.

The transmission antennas of transmitting stations and base stations,the reception antennas of terminals and the one antenna described in thedrawings may include a plurality of antennas.

Note that a program for executing the above-described communicationmethod may be stored in a ROM (Read Only Memory) in advance, and a CPU(Central Processing Unit) may be caused to operate this program.

Moreover, the program for executing the above-described communicationmethod may be stored in a computer-readable storage medium, and theprogram stored in the storage medium may be recorded in a RAM (RandomAccess Memory) of a computer, and the computer may be caused to operateaccording to this program.

Then, each configuration of each of the above-described exemplaryembodiments and the like may be realized typically as an LSI (LargeScale Integration) which is an integrated circuit. These integratedcircuits may be formed separately as one chip, or may be formed as onechip so as to include all or part of the configuration of each exemplaryembodiment. Although the LSI is described here, the integrated circuitis also called an IC (Integrated Circuit), a system LSI, a super LSI andan ultra LSI depending on the degree of integration. Moreover, atechnique for circuit integration is not limited to the LSI, and may berealized by a dedicated circuit or a general purpose processor. Aftermanufacturing of the LSI, a programmable FPGA (Field Programmable GateArray) or a reconfigurable processor which is reconfigurable inconnection or settings of circuit cells inside the LSI may be used.

Further, as a matter of course, when development of a semiconductortechnology or another derived technology provides a technology ofcircuit integration which replaces the LSI, functional blocks may beintegrated by using this technology. Adaptation of biotechnology or thelike may be possible.

The present disclosure is widely applicable to a wireless system whichtransmits different modulated signals from a plurality of antennas.Moreover, the present disclosure is also applicable in a case where MIMOtransmission is performed in a wired communication system having aplurality of transmission locations (for example, a PLC (Power LineCommunication) system, an optical communication system, and a DSL(Digital Subscriber Line) system).

The transmission method, the reception method, the transmission deviceand the reception device according to the present disclosure can securehigh data reception quality because of high error correctionperformance.

What is claimed is:
 1. A transmission method, executed by a transmittingapparatus, the transmission method comprising: selecting one codingscheme from a predetermined coding scheme set, the predetermined codingscheme set including two or more coding schemes having different codelengths for each of a plurality of coding rates; encoding an informationsequence according to the selected coding scheme to obtain an encodedsequence; modulating the encoded sequence to obtain data symbols; andtransmitting a transmission frame that carries the data symbols, whereinthe predetermined coding scheme set includes at least a first codingscheme and a second coding scheme, when the first coding scheme isselected, the coding includes generating a first codeword of a firstlength as the encoded sequence by using a first bit sequence inputted asthe information sequence according to a first parity check matrix, andwhen the second coding scheme is selected, the coding includesgenerating a second codeword of a second length longer than the firstlength by using a second bit sequence inputted as the informationsequence according to a second parity check matrix different from thefirst parity check matrix, and discarding a part of parity bits of thesecond codeword to generate a third codeword of the first length.
 2. Areception method, executed by a reception apparatus, the receptionmethod comprising: acquiring information indicating a selected codingscheme which is used for generating an encoded sequence from aninformation sequence, the encoded sequence being carried in a receivedsignal, the selected coding scheme being selected from a predeterminedcoding scheme set, the predetermined coding scheme set including two ormore coding schemes having different code lengths for each of aplurality of coding rates; demodulating a received signal, to obtaindemodulated values corresponding to the encoded sequence, based on aphase changing method that is applied to at least one of first modulatedsymbols and second modulated symbols generated from the encodedsequence; and decoding the demodulated values according to a decodingscheme corresponding to the selected coding scheme to obtain a receiveddata, wherein the predetermined coding scheme set includes at least afirst coding scheme and second coding scheme, when the informationindicates that the selected coding scheme is the first coding scheme,the encoded sequence is generated by generating a first codeword of afirst length as the encoded sequence by using a first bit sequenceinputted as the information sequence according to a first parity checkmatrix, and when the information indicates that the selected codingscheme is the second coding scheme, the encoded sequence is generated bygenerating a second codeword of a second length longer than the firstlength by using a second bit sequence inputted as the informationsequence according to a second parity check matrix different from thefirst parity check matrix, and discarding a part of parity bits of thesecond codeword to generate a third codeword of the first length.
 3. Atransmission apparatus, comprising: an encoder that, in operation,selects one coding scheme from a predetermined coding scheme set,encodes an information sequence according to the selected coding schemeto obtain an encoded sequence, the predetermined coding scheme setincluding two or more coding schemes having different code lengths foreach of a plurality of coding rates; a modulator that, in operation,modulates the encoded sequence to obtain data symbols; and a transmitterthat transmits a transmission frame that carries the data symbols,wherein the predetermined coding scheme set includes at least a firstcoding scheme and a second coding scheme, when the first coding schemeis selected, the coding includes generating a first codeword of a firstlength as the encoded sequence by using a first bit sequence inputted asthe information sequence according to a first parity check matrix, andwhen the second coding scheme is selected, the coding includesgenerating a second codeword of a second length longer than the firstlength by using a second bit sequence inputted as the informationsequence according to a second parity check matrix different from thefirst parity check matrix, and discarding a part of parity bits of thesecond codeword to generate a third codeword of the first length.
 4. Areception apparatus comprising: an acquisition unit that, in operation,acquires information indicating a selected coding scheme which is usedfor generating a encoded sequence from a information sequence, theencoded sequence being carried in a received signal, the selected codingscheme being selected from a predetermined coding scheme set, thepredetermined coding scheme set including two or more coding schemeshaving different code lengths for each of a plurality of coding rates; ademodulator that, in operation, demodulates a received signal, to obtaindemodulated values corresponding to the encoded sequence, based on aphase changing method that is applied to at least one of first modulatedsymbols and second modulated symbols generated from the encodedsequence; and a decoder that, in operation, decodes the demodulatedvalues according to a decoding scheme corresponding to the selectedcoding scheme to obtain a received data, wherein the predeterminedcoding scheme set includes at least a first coding scheme and secondcoding scheme, when the information indicates that the selected codingscheme is the first coding scheme, the encoded sequence is generated bygenerating a first codeword of a first length as the encoded sequence byusing a first bit sequence inputted as the information sequenceaccording to a first parity check matrix, and when the informationindicates that the selected coding scheme is the second coding scheme,the encoded sequence is generated by generating a second codeword of asecond length longer than the first length by using a second bitsequence inputted as the information sequence according to a secondparity check matrix different from the first parity check matrix, anddiscarding a part of parity bits of the second codeword to generate athird codeword of the first length.